<!DOCTYPE html><html lang="en"><head><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>Border</title><link rel="stylesheet" type="text/css" href="../test.css"></head><body><div class="tt"><div class="test">ttttt</div><div class="border-box">inner</div></div><div class="tt2"><div class="box"><div class="box-flex">inner</div><div class="box-flex">inner</div><div class="box-flex2">inner</div></div></div><div class="layout-demo"><div id="header" class="inner-padding border box-sizing">Hearder content</div><div id="content" class="clearfix"><div id="left" class="aside inner-padding border box-sizing">Left side</div><div id="main-content" class="article inner-padding border box-sizing">Main content</div></div><div id="footer" class="inner-padding border box-sizing">footer content</div></div></body></html>